Aircraft



D, M. BERGES Nov. 30, 1937.

AIRCRAFT Filed Feb. 5, 1936 T0 RIG/'17' A/LERON T0 LEFT A/LERON INVENToR. Dona/a7 M. eryes BY 'hun' Patented Nov. 30, 1937 PATENT OFFICE AIRCRAFT Donald M. Berges, Bloomfield, N. J., assgnor to Eclipse Aviation Corporation, East Orange, N. J., a corporation of New Jersey Application February 5, 1936, Serial No. 62,516

3 Claims.

This invention relates to aircraft, and particularly to the control of the craft's attitude during flight.

y An object of the invention is to provide for the 5 automatic return of the craft to a normal flight attitude, following an atmospherically induced departure therefrom.

A further object is to secure greater smoothness of operation in an attitude correcting system of the type characterized by the provision of a plurality of differentially connected pendulous bodies as the agency for initiation of the correcting operation.

In the embodiment illustrated in the accompanying drawingthe greater smoothness of operation is secured by the addition of means .including light sensitive correcting devices and oscillatory follow-up, means for controlling the energization of the light-sensitive devices; but it is to be expressly understood that' the drawing is for the purpose of illustration only, and is not designed as a definition of the limits of the invention, reference being had to the appended claims for this purpose.

In the drawing;

Fig. 1 is a. schematic representation of the preferred embodiment of the invention;

Fig. 2 is a mechanical view, partly in section,

of the control mechanism used in the embodiment of Fig. 1; and

Fig. 3 shows the control mechanism in one of its operating positions.

Reference characters 3 and 4 designate windings constituting the field elements of magnets, relays or motors having armatures 5 and 6, respectively; reference characters 'I and 8 designate thermionic, or electronic discharge tubes, characters 9 and I0 indicate photo-electric cells, charactersl I I, I2, and I3 indicate resistors, and character I4 indicates a source of current, of suiiicient power to energize tubes 1 and 8. A second source 2l supplies current .to one or the other of a pair of solenoids 22 and 23 of a servo-motor 20, upon closure of the corresponding switch contact cars ried by armatures 24, 25 respectively, of relays 29 and 30, which are in turn controlled (as to their energization) by armatures 5 and 6, re- A spectively.

Rods 45, 4B may be part of the usual manually 50 actuated aileron shifting linkage, but are prilmarily operable by servo-motor 20 corresponding to servo-motor 22 oi the -Havill application No. 636,605 of October 6, 1932 resulting in Patent No. 2,030,986 of February 18, 1936. (As in the Havill 55 application, aileron shifting rods 45, 46 will be manually operable, when desired for turning or banking purposes, even though the present invention is superimposed thereon.)

A light source L is adapted to cast light through" one or the other cf two openings 3I, 32 5 in a cylinder 34, the light falling on one or the other-of the two photo-electric cells 9, I0. Surrounding the cylinder 34 (constituting, in this embodiment, part of the follow-up device above referred to) is a second cylinder 33 having a radial slot 35 adapted to register with one or the other of the openings 3 I 32 but normally out of registry with said openings (as shown), thereby normally cutting oi all the light of lamp L from photoelectric cells 9 an`d I0.

Cylinder 34 has an extension 38 (Fig. 2) the lower end of which is engaged by a spring 39 anchored to the fuselage as shown at 4I, thus tending to hold the cylinder 34 in the central position indicated in Fig. 1, but nevertheless yieldable to permit swinging of the cylinder to either side when the rolling of the aircraft becomes sufilciently pronounced, this action being similar to that described for the cradle I5 and spring I6 in the Havill application No. 57,979 iiled January 7th, 1936.

The protruding portions 53 and 54 (Fig. 2) of the cylinder 34are mounted in suitable bearings on the aeroplane, and form a. cradle which undergoes a shift in position about its own axis in response to any shift in the angular position of the fuselage about the longitudinal axis, and cylinder 33 will also partake of a certain degree of this angular shift, although tending to remain in the true vertical position due to the weighted, pendulous tail 48 thereon. Therefore a rolling of the ship in either one direction or the other will cause a movement of the cylinder 34 to allow the light of lamp L to fall on the corresponding photo-electric cell. Light falling on either photoelectric cell causes a decrease in the grid bias of A one of the vacuum tubes l, 8 (depending upon which photo-electric cell is energized). This decrease in grid bias causes increase in plate current, which in turn causes one of sensitive relays 3, 4 to operate one of the two main relays 29, 30. These main relays close the circuits to the respective oil valve solenoids of servo-motor 20, the piston of which is connected (as in Havill application No. 636,605) to the ailerons in ysuch man- 50 ner as to vary the wind pressure upon the aerofoil surfaces of the plane in a direction to compensate for the atmospheric disturbances which produced the rolling (banking) movement of the plane.

Reference character 56 indicates a dashpot ef- 55 fective to damp the vibrations of the pendulum 48 by reason of the connection to the said pendulum through the link 51, one end of which attaches to the pendulum and the other end to the plunger rod 58 of the dashpot, the amount of restriction whereof may be adjustable by any suitable means. A similar dashpot 60 for providing a damping effect upon the cylinder 34 connects with said cylinder through a link 6| attached to the plunger rod 62, and its setting is such as to restrain movement of cylinder 34 to a greater extent than that of dashpot 56 upon cylinder 33.

Rolling of the craft in a clockwise direction, for example, will produce a clockwise shift of inner cylinder 34, together with its spring 39, thus moving passage 32 toward a position of registry with port 35. When this position of registry is attained (and assuming continued rolling of the craft in the clockwise direction) pins will engage the end surfaces of slots 52, whereupon the continuedshift of cylinder 34 is prevented by the weighted pendulous portion 48 of cylinder 33, thusmaintaining registry between passages 32 and 35, which registry results in continued energization of photo-electric cell 9 (the latter having been correspondingly shifted in a clockwise direction also) and a resultant shift of aileron controls 45, 46, through the action of the circuits (above described) in producing energization of solenoid 22.

Eventually this shift of the ailerons will halt the clockwise roll of the craft and hence the clockwise shift of the cylinders 34 and 33. Following this halt the craft will roll back in the opposite direction and cylinders 34 and 33 will start back toward their normal positions (Fig. 1) but due to the unequal effects of the dashpots 60, 56, cylinder 34 will be shifted back with slightly greater alacrity, thus shifting pins 5| to the opposite ends of slots 52, whereupon cylinder 33 is carried along also, but at a retarded rate, due to the greater drag rexerted by dashpot 60. Meanwhile this reverse swinging has drawn passage 3l into registry with port 35, to energize the correspondingly shifted photo-electric cell I0, the parts being now in the positions indicated in Fig. 3. The resulting energization of solenoid '23 restores the ailerons to a position approximating the neutral, the extent of the restoration depending upon the time elapsing before ports 35 and 3l again move out of registry with photo-electric cell l0 (the extent of swing of the latter being the saine as that of the fuselage). Meanwhile the reverse shifting ofthe ailerons tends to restore the craft to normal flight attitude, thus moving the cells 9, I0 back toward the positions'shown in Fig. 1. Should the craft continue to roll sufficiently beyond this position, the photo-electric cell 9 will again be energized to repeat the cycle of events, such repetition continuing until normalcy is established; but -with each subsequent cycle of shorter extent until nallythe action is completely damped out in accordance with the law vof damped harmonics. In this connection it will be observed that the differential action of the cylinders 33, 34 reduces the likelihood of over-control or too drastic shifting of the aileronsthat is, a shifting through an arc greater than that required to correct the condition which brought about departure of the craft from its normal flight attitude; this being due to the relative movement which can occur as between the cylinder 34 and the cylinder 33 as a direct result of the swaying of the craft.

What I claim is:

1. In an aircraft of the type in which portions of the crafts exposed surface are actuated as the means of controlling the flying attitude of the craft, the combination with said surface portions of electromagnetic actuating means therefor, a pair of inter-engaged telescoped cylinders means of controlling the flying attitude of the' craft, the combination with said surface portions of electromagnetic actuating means therefor, means including a pair of telescoped cylinders controlling energization of said electromagnetic means said controlling means also including a source of light within said cylinders, and external photo-electric means shiftable both with and differentially of the inner cylinder to receive light passing therethrough.

3. In an aircraft of the type in which portions of the crafts exposed surface are actuated as the means of controlling the flying attitude of the craft, the combination with said surface portions of electromagnetic actuating means therefor, means including a pair of pendulous telescoped cylinders movable in unison and differentially for controlling energization of said electromagnetic means said controlling means also including a source of light within said cylinders, and photo-` DONALD M. BERGES. 

